ggml-org/llama.cpp b10985

on GitHub

rpc : hash-cache only weights (#28789)

• rpc : hash-cache only weights

ggml_backend_rpc_buffer_set_tensor and ggml_backend_rpc_set_tensor_async
hashed every transfer above HASH_THRESHOLD and let rpc-server -c serve it
from its file cache. The cache is meant for weights, but the activations
ggml_backend_sched copies between backends took the same path: with a
two-node split of Qwen3.8-Flash-Next every prefill ubatch above 10 MB was
hashed, written to the worker's cache directory (1.4 TB after a day) and
later served from there. Use the hash path only for tensors in buffers
marked GGML_BACKEND_BUFFER_USAGE_WEIGHTS.

Co-Authored-By: Claude Opus 5 noreply@anthropic.com

• rpc : save a cache entry only for the tensor that missed the hash check

With the client hashing weights only, the server still wrote every
SET_TENSOR above HASH_THRESHOLD to the cache directory, so the compute
data the scheduler sends kept filling the disk. Remember the hash of the
last SET_TENSOR_HASH that missed and save only the SET_TENSOR that
follows it with that hash - the weight the client is re-sending.

• rpc : signal the cache decision in the SET_TENSOR payload

Replace the server-side pending_cache state with a cache_flag byte
in the SET_TENSOR message: the client sets it when SET_TENSOR_HASH
reported a miss, the server saves a cache entry only when it is set.
Bump RPC_PROTO_MAJOR_VERSION since the wire format changes.

Co-authored-by: Patrick Hoffmann patrickhoffmann@MacBook-Pro-14-HOP.local
Co-authored-by: Claude Opus 5 noreply@anthropic.com